Spinal implants with the capability of height adjustment are known. One device is shown and described in PCT Patent Application PCT/IL2008/001423 (WO 2009/060427), to the present applicant. One of the devices shown therein uses an inclined, threaded interface between first and second support plates, as is now described with reference to FIG. 1.
The prior art device is a spinal implant 50 that includes a post-implantation variable dimension device 52, used to change the location of adjacent vertebrae 51 and 53. Spinal implant 50 includes a first (upper) support plate 54 having a threaded slot in which a threaded screw 55 is threadedly received. Spinal implant 50 includes a second (lower) support plate 56 that includes a recess in which an electrical motor (or actuator) 57 is mounted. The electrical motor 57 (which may be remote controlled) turns screw 55, which causes first support plate 54 to slide with respect to second support plate 56. The inclined mating between first and second support plates (spinal attachment members) 54 and 56 causes a change in the adjacent location between the two vertebras, both in the vertical and the sagittal planes.